Manually operated photofluorographic camera



June 13, 1950 R. H. DRAEGER ETAL 2,510,965

MANUALLY OPERATED PHOTOFLUOROGRAPHIC CAMERA Filed Aug. 29, 1945 5 Sheets-Sheet 1 Figure I.

02W W laegm 3 June 13, 1950 R. H. DRAEGER ErAL MANUALLY OPERATED PHOTOFLUOROGRAPHIC CAMERA Filed Aug. 29, 1945 3 Sheets-Sheet 2 Figure 2 J1me 1950 R. H. DRAEGER 'ETAL 2,

MANUALLY OPERATED PHOTOFLUOROGRAPHIC CAMERA Filed Aug. 29, 1945 3 Sheets-Sheet 3 Patented June 13, 1950 MANUALLY-PERAKBED PHOTOFLUORO- GRAPHIC CAMERA Rupert .H. Draeger and-HaroldE. A..Long,- United StatesNavy Application August 29, 11945, SerialNo. $613,402

(Granted under the act of March *3, "1-883, as

amended :April 30, 1928-; 370 --O. -G. 757

1 Claim.

1 'Thisinvention relates to a photofiuorographic camera more particularly to a manually operated camera especially adaptedto microphotography or photofiuorography.

'Photofiuorography*maybe defined as the-art i of photography of .the X-ray fluorescent screen. Radiography employs a photographic'film ofsubstantially the same size as the object being X-rayed. For example, radiography of'theches-t ordinarily employs a"14 x 17inch 'X-ray film. It is thus apparent that the film cost in radiography is directly proportional to'the size of the object being X-rayed. Furthermore, because of this large size,'the cost of film "processing is'high and'filing space is excessive.

It is an object of this "invention to'provide a photofiuorographic camera utilizing miniature film, thus reducing the film cost "heretofore incident to clinical and industrial 'X-ray examinations.

Another object of the invention is to provide a simple, compact, manually operated camera which is readily detachable from a photofiuorographicX-ray unit for reloading.

A further object "is to "devise aportable-compact manually operable photofiuorographic camera which may employ a sufficient quantity of film to make frequent reloading unnecessary.

It will beappreciated that the photographyof the X-rayfluorescentscreenby a miniaturecamera will result in amarked saving of film. For example, whereas the cost of a 14 X 17 inch X-ray film -is of the order of "60 cents,the'cost'of-a"35 mm. photofiuorographic -film*to makethe equivalent photograph is only about '1 cent. --'I-he-filing space required for the processed --films is, --of course, directly proportional -to their relative sizes.

While thereare a-number of obvious advantages to photofiuorography it does present certaininherent difficulties. The low light intensity of the fluorescent screen requires a correspondingly fast photographic lens and an appreciably longer X-ray exposure to obtain a satisfactory -photographic image. There is also some inherent loss of detail involved in forming an image of a fluorescent screen upon the photographic negative.

Ithasbeensuggested heretofore toutilize miniature camerasfor photofiuorography. :However, sincesuch cameras normally hold but a limited supply of film considerable attention and fre quent reloading would berequired.

The fundamental principleof I the invention involves the useofasimple manually operated miniature camera especially designed to successively photograph images of the 'X-ray fluorescent screen.

The -fu-ndamental principle of the invention and-the novel features of construction and design of the camera will be-more readily appreciated and evaluated from the consideration of a pre- *ferred physical embodiment such as is shown in the accompanying drawings in-which:

*Fig. lis -a perspective view of the photofiuorographic unit -Fig.-2'is a. perspective view cf-'theinterior of the camera as-seenfromthe front, and

Fig. '-3-is a perspective view of the camera as seen-from the rear 'with the back plate cut away.

As will be seen in Fig. 1, the photofiuorographic unitcomprises'essentially an'X ray-tube-mounted for vertically adjustable movement upon the standard *2. *The'tube [is electrically connected bythecablesd and 4 in the-usualmannerto the X-ray transformer and control stand ('not shown).

A liglit ti-ght truncated box -5 is "mounted for vertically adjustable movement upon the standard 6. The movement of 'the -X-ray-'-tube -l "and the cone '5 *are synchronized by 'means 'of the cables and 8. This movement is effected'by means of the hand wheel =9, mounted for vertical-movementwith-the cone 5. *TheconeS-is-associated atdtsdarger-end with an X-ray fluorescent-screen l0 and at its smaller'end with a support plate H which *is: adapted to carry the camera-l-2. lhe plate-H is lormedwith an aperture having a light-tight bushing to receive the lens of camera t2. Ehe camera, as -willbe seen, rests upon the mounting bracket reattached to supportp'late H 'l he patient 0r-subject i4 is-shown in a positionbefore the fluorescent screen in the usual manner for radiography.

The -photofiuorographiccamera -!-2 comprises essentially :a light-tight case or compartment 4-5 of any suitable constructiomor design which :is closed-by the hingedcdoor 11-6. The camera is provided with the photographic lens all which is adapted to focus on film =18 inthe :film gate 49. Theyfilm i8is retained in the film gate bymeans of the plate i241 andis supported .by the .movable arm :21, The arm 2| istintegrally.attachedto the collar ;22.-.whichzlatterzisrotatably mounted upon the shaft 23. llhe collar 2-2 is provided-with a pin :24 connected to .one end .of the .spring 25. As shown,athe.-other enclof thestension spring ;is attached tothe spring post 26. .As will ;be ..observed, the .tension spring 25 operates through arm 2 l to hold the =reta'ining :plate :20 .and indirectly, the :film IB in-its properposition in the film gate. As will be seen, the extension 21 provides a means for readily opening the film gate for insertion of the film.

A film roll as with a center spool 30 is rotatably mounted upon the shaft 3|, and is supported by magazine half-spool 32. The door It is provided with a plate which opposes half-spool 3'2 and serves to retain the film roll 29 upon the magazine spool when the camera door is in closed position.

One of the several improved features of the present invention is the provision of means for indicating the quantity of film remaining on magazine film roll 29. This unit comprises essentially the curved arm 34 which is pivoted at one end for rotation upon the shaft 35. The other end of the arm 35 is provided with the idler roller 35 and extension boss 31 by means of which the arm 3 is withdrawn so as to permit the insertion of a film roll on shaft 3|. The curved arm 34 is formed with an integral extension 38 provided with a spring post 39 to which is attached one end of spring ill. The other end of the spring ill is connected to a spring post 4| which latter acts as a stop for the lever 42.

The shaft 35 which carries the arm 34 is provided with an indicator pointer 13. Since this pointer is attached to the shaft 35 and moves with the arm 35, it serves to visually indicate the quantity of film remaining on the magazine film roll 29. As shown, the pointer 53 is located outside of the case for easy and ready inspection. A dial face may be associated with the pointer to indicate the quantity of film remaining on the spool.

The take-up mechanism comprises the shaft 53, one end of which is journaled in a bearing attached to the side wall of the camera opposite the door 95. The shaft 56 extends through this side wall and on the outside is provided with a knurled knob (not shown) whereby the shaft 56 may be manually operated. The shaft 50 has keyed thereon a spur gear 5| and an adjacent take-up half-spool plate 52. The shaft 56 extends beyond the plate 52 and provides the shaft extension 53 upon which the take-up film spool 54 is mounted. The end of shaft 53 is threaded to receive the plate 55. This plate is furnished on one side with a screw for engaging the corresponding threads on the shaft 53 and on the opposite side with an integral knurled knob 55 whereby the plate may be readily attached or removed. As will be appreciated, the plate 55 serves to hold the film magazine roll 5A in position upon the film take-up shaft 53. The film take-up spool 54. is provided with apertures 56 adapted to receive pins (not shown) attached to the plate 52.

As will be seen from Fig. 2, film from the magazine spool 29 passes over idler roller 51 which is freely rotatable upon shaft 23. The film passes through the film gate and over the opposite idler roller 58 and then over the pressure roller 56 and associated idler roller 69 to the take-up spool 54. The pressure roller 59, as shown in Fig. 3, is attached to the disc 5| by means of the hollow extension 62. The pressure roller 59, disc 6| and connecting extension 62 are freely rotatable upon the shaft 49. Shaft 49 is attached to the boss 63 having a threaded portion 54 by which means it may be attached to the camera back plate by a screw (not shown).

The camera is provided with an improved simplified film advancing mechanism. This comprisesthe association of the spur gear 5|, the

notched disc 6|, and the lever 65. The lever 65 is attached to the shaft 66 and is adapted to be rotated therewith. The shaft 66 is supported in a bearing (not shown) attached to the back plate 57 of the camera and extends through this plate to the outside of the camera and terminates in an attached knob (not shown) whereby it may be manually rotated. The lever 65 is formed at one end with the detent 66 adapted to engage the notches 69 of disc 6|. The opposite end of the lever is provided with rack teeth lo adapted to engage the teeth of spur gear 5|. There is also provided at this end of the lever the pawl ll mounted for pivotal movement upon the pin 12. One end of the pawl is attached to the tension spring 13, the other end of which is attached to the plate 14 fixed to the lever 65. This plate carries the spring post 15 to which one end of tension spring 16 is attached. The other end of this spring is attached to the spring post 11 which is secured to the back plate 61. counterclockwise rotation of spur gear 5| is prevented by means of pawl 78 which is mounted for rotation upon a support it. The coil spring 85 serves to press the rack teeth of the pawl into contact with spur gear 5|.

The operation of the simplified film advancing mechanism will be appreciated from the foregoing description. Manual rotation of the extension knob attached to shaft 66 causes pivotal movement of lever 65 and disengagement of detent 66 from disc 6| and rack teeth 1|] from spur gear 5|. As will be noted, as the lever is rotated the spring pressed pawl H will assume a perpendicular position with relation to the lever 85 and prevent the reengagement of the rack teeth it or detent 68. Clockwise rotation of shaft 56 effects rotation of the spur gear 5i and associated take-up spool 54 to move an additional unexposed portion of film into the film gate. Rotation of spur gear 5| rotates pawl ll disengaging it from the spur gear 5| allowing lever 55 to rotate until the detent 55 rests upon the periphery of the disc 6i and finally engages the opposite notch 59, thus insuring the proper amount of film being advanced into the film gate. As detent 68 engages notch 69 rack teeth 10 will likewise reengage spur gear 5|, thus locking the film advancing mechanism. As will be appreciated, the film advancing cycle thus involves the successive clockwise rotation of the shafts 66 and 50.

Another improved feature of the invention is the provision of a mechanical interlock mechanism whereby the film advancing mechanism is rendered inoperable when the film magazine supply is almost exhausted. This feature is accomplished by the extension 38 of the film indicator mechanism. As the film magazine roll diminishes in diameter the arm 38 and idler roller 36 are rotated about shaft 35. As will be seen, when the arm 38 rotates to a predetermined position below the end of lever 65 pivotal movement of said lever is prevented thereby locking the entire film advancing mechanism and indicating to the operator that the film supply needs to be replenished.

It will thus be seen that the photofiuorographic camera herein described is as simple as it is effective. The unit comprises essentially only a minimum of moving parts to control the advancement of film in the film gate and to provide an interlocking mechanism when the camera is out of film. The novel association of the lever 65 withthe disc 6| insures the advancement of a predetermined quantity of film in the film gate regardless of the amount of film on either the magazine or the take-up spool. The depletion of film is simply and effectively indicated by pointer 43 with a simplified mechanism.

It is apparent therefore that eminent simplicity of mechanism is insured by the performance of a plurality of functions by the several mechanical elements involved.

It is apparent that the camera structure is susceptable of considerable modification for the purpose of accomplishing any desired supplemental functions. For example, a shutter mechanism may be incorporated and the camera employed for microphotography or other uses.

While a preferred embodiment of the invention has been shown and described it will be understood that this is given to illustrate the particular principles involved and not as limiting the useful scope of the invention to the chosen illustrative embodiment.

The invention'described herein may be manufactured and used by or for the Government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

We claim:

A camera comprising a housing, a film gate within the housing, a film magazine roll, a film take-up roll comprising a shaft having a ratchet mounted thereon. said shaft projecting through the housing and provided with a manually operable knob, a pressure roller interposed between the take-up spool and the film gate, said pressure roller being provided with a notched disc, a lever pivotally mounted upon a shaft, said shaft extending through the housing and provided with a manually operable knob, one end of the lever being provided with ratchet teeth for engagement with the ratchet of said take-up mechanism and the other end of the lever being formed with a dog adapted to engage the notches in the disc of the pressure roller, a spring pressed pawl pivotally mounted on an end of the lever adjacent to said ratchet and adapted to retain said lever in a disengaged position when said lever has been manually disengaged, said pawl being adapted to being released when the ratchet of the take-up mechanism is rotated and a spring pressed pawl adapted to prevent counterclockwise rotation of the ratchet of the take-up mechanism.

RUPERT H. DRAEGER.

HAROLD F. A. LONG.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,744,773 Labrely Jan. 28, 1930 1,806,763 McCarthy May 26, 1931 1,897,903 Hopkins Feb. 14, 1933 1,957,889 Hopkins et a1. May 8, 1934 1,974,842 Black Sept. 24, 1934 2,063,331 Nagel Dec. 8, 1936 2,090,017 Young, Jr. Aug. 17, 1937 2,131,926 Weiblen et al. Oct. 4, 1938 2,139,759 Lindenberg Dec. 13, 1938 2,150,696 Nelson Mar. 14, 1939 2,351,999 Nerwin June 20, 1944 2,358,327 Harris Sept. 19, 1944 FOREIGN PATENTS Number Country Date 591,215 France Apr. 4, 1925 563,304 Great Britain Aug. 9, 1944 

